Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
2021 Lexus RX 450h BaseFACTORY OEM SERVICE PROCEDURE
Road Sign Assist System
ROAD SIGN ASSIST SYSTEM DIAGNOSTIC TROUBLE CODE (DTC) IDENTIFICATION
| DTC Code | Description |
|---|---|
| U0125-87 | Lost Communication with Multi-axis Acceleration Sensor Module Missing Message |
| U0129-87 | Lost Communication with Brake System Control Module Missing Message |
| U0140-87 | Lost Communication with Body Control Module Missing Message |
| U0155-87 | Lost Communication with Instrument Panel Cluster (IPC) Control Module Missing Message |
| U0293-87 | Lost Communication with Hybrid Powertrain Control Module Missing Message |
Factory Service Tools
Use the Manual With the Right Hardware
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.